# description
Put one contact into a sequence by hand. The sequence must be `active`. A suppressed address, or one already in flight on a `reentry: "once"` sequence, is refused with 409 rather than silently ignored.

# properties.email.description
The address to enroll. Give this or `contactId`.

# properties.contactId.description
A contact you own (ctc_…), as an alternative to `email`.

# properties.from.description
Sender for this enrollment, when the sequence has no default (a send-triggered sequence normally inherits one from the triggering message, which a manual enroll does not have).

# properties.input.description
The sequence's input, checked against its declared signature. A missing required field refuses the enrollment and says which — you find out here rather than days later as a blank merge tag.

# properties.data.description
The original name for `input`. Still accepted; `input` wins when both are given.

# properties.cancelKey.description
Your own key for this enrollment. Cancel later with POST /v1/enrollments/cancel and this key — no need to store our id.